Prosecutors are considering building criminal cases in January against accountants of two factions of the ruling Liberal Democratic Party over a political fundraising scandal, prior to the start of the ordinary Diet session, sources close to the matter said Sunday.

As prosecutors deepen their probe into allegations that the factions created slush funds through off-the-book revenues earned from fundraising parties, they are also considering whether to build cases against two LDP lawmakers who are suspected of receiving tens of millions of yen under the scheme.

The factions in question are the LDP's biggest, the 99-member group formerly led by the late Prime Minister Shinzo Abe, and another led by former LDP Secretary General Toshihiro Nikai.

To limit the impact of a criminal investigation on parliamentary discussions, prosecutors usually decide to build criminal cases while the Diet session is closed when politicians or their aides are involved.

Photo taken Aug. 30, 2020, shows the Liberal Democratic Party headquarters in Tokyo.

The government and the ruling coalition of the LDP and Komeito party are making arrangements to convene the 150-day regular Diet session either on Jan. 22 or Jan. 26, the sources said.

The Political Funds Control Act requires an accountant to submit a report on income and expenditures, and a failure to report can be punishable by imprisonment for up to five years or a fine of up to 1 million yen. Lawmakers could also face criminal charges if suspected of colluding with accountants.

At question in the scandal are funds raised by lawmakers for selling tickets for faction events beyond their assigned quotas. Such excess funds have allegedly not been recorded in the political funds report, and transferred to the lawmakers.

The Abe faction had not reported the transferred funds as expenditure, and the lawmakers who received the money had also not recorded them as income. The sum of the funds is believed to have amounted to around 500 million yen ($3.5 million) over a five-year period through 2022.

The Nikai group also had not reported funds that were earned from ticket sales beyond quotas, with the sum suspected to have totaled over 100 million yen over the same five years. But the money that was passed on to lawmakers was recorded as either expenditure or income by the faction and lawmakers.

The prosecutors have been stepping up their investigation since the extraordinary Diet session ended in mid-December, searching the offices of the two factions and questioning key Abe faction members on a voluntary basis, including former Chief Cabinet Secretary Hirokazu Matsuno and former trade minister Yasutoshi Nishimura.

While looking into the potential role senior faction members have played in the scandal, prosecutors also seem to be targeting lawmakers who received large sums.

Most of the Abe group members are suspected to have received the backdoor funds, but the cases of House of Representative member Yoshitaka Ikeda and House of Councillors member Yasutada Ono stand out as they are suspected of receiving over 40 million yen and 50 million yen, respectively.

The prosecutors have already searched locations linked to the two lawmakers.

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